Polishing machine



April 5, 1938.

E. FAB'ER POLISHING MACHINE Filed May 20, 1936 E. /nvem or:

Patented -Apr. 5, 1938 UNITED STATES PATENT OFFICE 2.113.4 1; romsnmo. MAcHmE Ernst Faber, Stuttgart, Germany I Application May 20, 1936, Serial No. stars In Germany June 4, 1935 tion, for firmly securing the handle in its upright inoperative position, more particularly so that the machine when being put aside, when it is suitably carried by means of the handle, cannot through overbalancing fall over about the pivotal point of the handle and strike the ground. Such over-balancing is particularly likely to occur, when the handle is pivoted not in a central transverse axis of the machine casing, but externally of the middle, which is of advantage, since otherwise the machine is liable to have a jumping motion when in use.

According to the invention the object aimed at is realized by the provision of an extension of the motor casing, which is acted on by the weight of the motor or by the spring bearing against a fixed abutment and which, when the machineis not in use, that is when the handle is upright, bears against a projection on thehandle. At the same time the weight or the spring presses the extension of the motor casing against the projection on the handle which through its pivotal attachment to the casing oil'ers resistance, so that the machine can be grasped by the handle for placing it aside without it falling over in the manner explained above and the coupling of motor casing extension and handle projection becoming released. Furthermore, the handle is thus se-- cured in a reliable manner from becoming inadvertently released from its locked position through shocks or the like acting on it.

The accompanying drawing illustrates a constructional example of the arrangement according to the invention in a vertical section, partly in elevation.

at is the motor which is mounted so as to be capable of swinging by means of two gudgeons b disposed outside its centre of gravity in upper lateral wings c of the: substantially cylindrical casing d. e is the current lead and f is a driving pinion mounted on the motor shaft. This pinion is intended to coact with a rubber ring a bedded in the dished supporting body It surrounding the motor of a polishing disc 1. The supporting body It is arranged to rotate about a shaft k which is securely .journalled on the machine .casing d by means of abow member m whichemr braces the motor casing a frombelow. The bow member m at the same time forms a rigid abutment for a helical spring 12 which acts on an ex-1 5 tension 0 of the motor casing. This extension is also' constructed to form a treadle-p and is provided at its upper arcuate downwardly sweeping edge with a notch q, the object of which is to'coact with a pin-like projection r of the handle 8 for guiding the machine, more. particularly a cross-piece r of a bow-shaped extension t which is pivoted at either side of the machine casing on pins t.

"The drawing shows the machine in its inoperative position, that is with the handle erect, In this position the. canting weight of the motor and the spring n press the motor extension 0 against the projection r of the handle and hold the handle securely in its erect position, so that it is prevented in a reliable manner from sliding off the extension 0, either should the handle be knocked or more particularly, when the machine tor the purpose of placing it aside is grasped by the handle and is thus suspended from the handle 25 pivots t with an overbalancing weight on one side.

For putting the machine into operation the handle is brought into its inclined operative position. 'I'o eil'ectthis it is necessary, in order to bring the handle projection r out of the notch q, first to move the extension 0 downwards. For facilitating this operation the extension 0 is provided with aoplate p adapted to be depressed by the foot.

v i Instead oi. the spring thecanting weight of the motor which is suspended outside itscentre of gravity may sufllce, so that the spring may be omitted, or,-if the motor be suspended in its centre of gravity, the spring alone may be brought into 40 action.

What I claim is: I 1. In an electrically driven floor polishing machine in combination, a machine casing, a'drivlng disc rotatable in said casing, a polishing brush and the driving motor and arranged to tilt thesm driving motor to apply the driving pinion to the driving disc, a handle pivotally mounted on the machine casing so as to be capable of being swung from an inclined operative position into an upright inoperative position, a locking projection on the driving motor and a eo-operating locking projection on the handie arranged to engage the projection on the driving motor and displace the motor against the action of the spring; onthe handle being moved into the upright position, and thereby maintain the two projections under spring pressure in engagement with one another.

2. In an electrically driven floor polishing machine, in combination,'a machine casing, a driving disc rotatable in said casing, a polishing brush connected to said driving disc, a driving motor pivotally mounted on said casing-and having a driving shaft with a driving pinion thereon, a spring interposed between the machine casing and the driving motor and arranged to tilt the driving motor to apply the driving pinion to the driving disc, a handle pivotally mounted on the machine casing so as to be capable of being swungrfrom an inclined operative position into an upright inoperative position, a locking projection on the driving motor and a oo-operating locking projection on the handle arranged to engage -the projection on the driving motor and displace the motor against the action of the spring, on the handle being moved into the upright position, and thereby maintain the two projections under spring pressure in engagement with one another, the projection on the driving motor comprising a pedal for enabling the driving motor to be displaced against the action of the spring to release the projection on the motor i'rom the projection on the handle.

3. Inran electrically driven floor polishing machine, in combination, a machine casing, a driving disc rotatable in said casing, a polishing brush connected to said driving disc, a driving motor pivotally mounted on said casing and having a driving shaft with a driving pinion thereon, a projection on the driving motor on the end thereof remote from the driving pinion, a spring interposed between the machine casing and the driving motor and bearing against said projection so as to tilt the driving motor to apply the driving pinion to the driving disc, a handle pivotally mounted on the machine casing so as to be capable of being swung from an inclined operative position into an upright inoperative position, the projection on the driving motor having a notch therein and the handle having a locking projection thereon arranged to engage the projection on the driving motor and displace the motor against the action of the, spring, on the handle being moved into the upright position, and engage with said notch, whereby the handle is secured in the upright position under the pressure of the spring which maintains the-locking projection in engagement in said notch.

ERNST FABER. 

